Abstract: Steam power system is the core process of power plant for petrochemical、steel and thermoelectricity enterprises. Operation optimization can result in remarkable economic benefits of energy saving and environment protection. The Guangzhou Branch of Sinopec applied software of PROSS（Process Real Time Optimization for Steam System）by Beijing Yanzhijieneng Technology Corporation to simulate, analyze and optimize the working conditions of boilers and turbines, fuel configuration and steam equilibrium of the power plant. It is proved from the commercial results that with the PROSS technology the optimized production scheme of the power plant can be easily arranged, and operation cost reduction and good economic benefit can be obtained.